Precious stone



FIG. 1 is a side perspective view, showing my new design;

FIG. 2 is a right side view;

FIG. 3 is a left side view;

FIG. 4 is a front view;

FIG. 5 is a rear view;

FIG. 6 is a bottom view; and,

FIG. 7 is a top plan view. 

I claim the ornamental design for a precious stone, as shown. 